High voltage electrode housing



July 7, 1936.

s. c. MILLER HIGH VOLTAGE ELECTRODE HOUSING Filed Jan. 20, 1936 Patented July 7, 1936 UNITED STATES PATENT OFFICE Claims.

This application relates to insulators; more particularly to high voltage electrode housing insulators including contact mounts for neon tube signs In the mounting of an assembly of neon tube signs or similar decorative signs in which the parts are exposed to, the atmosphere, the contact portions adjacent the tube electrodes are mounted within insulator sockets of deep cup-shaped construction which are afiixed to a supporting body, usually of metallic frame work, to which the ground connection of the electrical system is connected. This insulator carries terminal contacts to which the electrode contacting portion of the neon tube is assembled. By reason of exposure to the weather, not only is it essential to include insulating material of high dielectric strength, but also the insulator must include means for the drainage of accumulated moisture and rain water.

Where I have utilized porcelain insulators for the purposes contemplated by me, the improvision of the contour permitting the inclusion of drain holes for accumulated moisture and rain water is a comparatively simple problem.

However, where I have employed so-called porcelain insulators, the general porosity of porcelain in the presence of the high intensity current employed makes this material objectionable in its use for the purposes above referred to.

While glass, specifically, the Pyrex type glass or that of hero-silicate composition, provides 7 an excellent insulator of proper dielectric qualities and density or freedom from porosity, its use for purposes contemplated by me was not commercially feasible, due to the inability to provide such essential details as proper insulating support of sumcient mechanical rigidity, as well as the drainage orifices which make continued operation under inclement weather conditions possible.

My invention makes possible the use of the Pyrex type or boro-silicate type of glass, as an insulator and terminal support which combines high electrical insulating qualities, as well as the mechanical function of supporting the terminal, while providing the necessary drainage facilities for moisture and water which is important in an outdoor tube sign construction.

For a clearer understanding of my invention, it may be noted that the utilization of glass, particularly the Pyrex type or boro-silicate type of glass, is advantageous in that the glass may be cast in molds, utilizing a plunger type of core.

The temperatures at which glass of this character is cast prohibits the use of small sized cores in order to form drainage orifices in the casting and which may remain in contact with the glass for any appreciable periodof time, with the molten glass at the high temperatures employed. This is due to the fact'that the material of the cores of small dimensions which must be utilized to form drainage orifices quickly deteriorates in the presence of the molten glass and limits'the use of these molds, to makeglass casting commercially impractica It is therefore an object of my invention to provide an insulator construction and terminal mount which will make glass, particularly the Pyrex or boro-silicate type of glass commercially available for insulator purposes, particularly in the formation of insulators and terminal mounts of the character contemplated by me for neon tube lighting purposes.

To attain the aforementioned objectives and such other objectives as will be apparent or more clearly appear as this description proceeds, I make reference to the accompanying drawing forming a part hereof, in which Figure 1 is a longitudinal sectional view through my electrode and terminal mount, showing a fragment of the housing to which the electrode is attached;

Figure 2 is a sectiontaken on the line 2-2 of Figure 1;

Figure 3 is a side elevation sectional view of my electrode of its manufacture.

Making reference to the drawing, Figure 1 illustrates a fragment of a neon sign frame it, having an orifice it through which a deep cupshaped electrode housing or insulator l2 arranged to be exposed to the weather is disposed, so that a flange i3 abuts the outer face of the plate i0, and cooperates with a screw-threaded collar M engaging the screw-thread it on the electrode housing it to bind the same to the plate.

This form of connection is more or less standard and of well-known design.

In connection with an insulator of this general type, it will be observed that there is provided a central boring it exposed'to the weather, through which the end of the neon tube sign carrying the electrode generally shown. at I? in dotted lines, passes. As atmospheric moisture and rain water and the like may enter this boring, drainage must be provided by suitable orifices.

In attempting to provide drainage orifices in and fragmentary blank at one stage porcelain insulators, no diificulty has been ex- The enlarged orifice thus provided not only serves as a drainage orifice for the purposes previously emphasized but also serves to support the electrode contact and terminal post portion of the electrical circuit.

In Figure l, I have shown a helical resilient spring contact l9, attached to the head 20, of a terminal post which is provided with a square shank 2i fitting within the cross-member 22 and rests against the inner wall 23 of the flange H. To the outer face 24 of the flange I'I, there is applied the spider 25 with a screw-threaded orifice 26 engaging the shank of the post and rigidly holds the post in the axial position.

It will be observed that from this construction, the electrode contact l9 is-given proper insulating assembly while providing a drainage orifice,.

thus combining mechanical rigidity, electrical insulation and drainage features. The construction as provided makes possible the use of glass, particularly the Pyrex type or bore-silicate glass type of material for insulating purposes, in an insulator for the uses contemplated by me.

For a clearer understanding of the method of production of the insulator, reference will now be made to Figure 3, showing the general configuration of a die cast plunger core type of blank which is convenient for forming the final insulator with the orifice for drainage purposes, as previously described.

The insulator in the form of a deep cup-shaped vessel having a central boring I6 is die cast with a bottom 30 and exterior offset shoulders 3i and an interior shoulder 32. The core plunger which outlines the boring I6 may include provision for forming the lugs 22a.

- This type of glass casting embodies the minimum use of heat resistant material and extreme simplicity of core outline; so that the mold and the core plunger may be used repeatedly without erosion, warping, burning or disfiguration of the mold and the core plunger.

After completion of the blank as shown in Figure 3, the bottom and offset portions 30 and 3|, respectively, are groundofl along the line :cy, to thereby provide the face 24, as shown in Figure I. This operation thereby provides the orifice i8 without the need of boring or drilling the glass.

-It will thus be observed that the nature of configuration of the insulator blank shown in Fi ure 3 is readily adaptable for die casting and plunger-core operation, permitting the use of glass for insulator purposes in a device of the character contemplated by me. Whereas the need for orificing the insulator would ordinarily make glass unavailable for the production of high voltage electrode housing for neon tubes, my construction makes such use of glass commercially feasible.

It will also be observed that I have provided a high voltage electrode housing or insulator for the purposes contemplated by 'me which combines efiicient insulating qualities with rigidity and simplicity of construction, having utility elsewhere where these features are desirable as will be readily understood by those skilled in the art.

While I have preferably shown the orificed portion ll formed in the bottom of the electrode housing l2 as the most preferable form with the type of casting operation described it will be understood that to some extent the location of the flange outlining the orifice for drainage and for mounting the contact and terminal may be positioned elsewhere for different forms of electrodes and casting operations for these forms.

It will also be observed that though my form of electrode housing or insulator has preferred use for insulators made of glass, the assembly. described by me has novelty of general utility for other insulator materials, and of broader scope .coming within the purview of the appended claims.

Having thus described my invention and illustrated its use what I claim as new and desire to secure by Letters Patent is 1. A high voltage electrode housing of insulating material having an-enlarged orifice for drainage when used for purposes described, crossmembers spanning said orifice, and supporting an electrode contact and terminal disposed through said orifice, said cross members, contact and terminal obstructing only a portion of said orifice, leaving substantially one-half the area of the oriflce for drainage.

2. A high voltage electrode housing of insulating material for the purpose set forth, comprising insulator glass formed with an inwardly directed flange adjacent to one end thereof defining a drainage orifice, cross bars disposed on opposite faces of said flange, and a terminal post for clamping saidbars in position and. supporting an electrode contact, said cross bars, post, and contact obstructing only a portion of said orifice and leaving a substantial passage for drainage.

3. A high voltage electrode housing of insulating material for the purposes set forth, comprising insulator glass formed with an inwardly directed flange adjacent one end thereof, defining a drainage oriflce, a terminal mounting and contact support maintained within said orifice, and cross members spanning said orifice andsupporting said terminal mounting, said cross members obstructing only a portion of said orifice and leaving a substantial passage for drainage.

4. A high voltage electrode housing of insulating material for the purpose described comprising a cast insulator of heat resisting borosilicate glass formed with an inwardly directed flange at one end thereof and continuous with the end of the side walls thereof, said flange defining a drainage orifice and constituting means for mounting a terminal and a support for a contact within said orifice in association with cross members spanning said orifice for supporting said terminal mounting and contact support and in which said cross members obstruct only a portion,

of. said orifice, leaving a substantial passage for drainage. F

5. In a high voltage electrode housing assembly for the purposes set forth, a housing of insulating material and which has an inwardly directed flange adjacent one end thereof defining a drainage orifice and constituting means for suspending a terminal mounting and contact support, maintained within said orifice by cross members spanning said orifice and supporting said terminal mounting, with said cross members obstructing only a portion of said orifice, leaving a substantial passage for drainage, said housing being formed of cast insulating and heat resisting glass, the inwardly directed flange being continuous with the end of the side walls of the housing. I

SAMUEL C. MILLER. I 

